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Google Analytics Dashboard for Preliminary map showing freshwater heads for the Red River Formation, Bighorn Dolomite, and equivalent rocks of Ordovician age in the Northern Great Plains of Montana, North Dakota, South Dakota, and Wyoming

Preliminary map showing freshwater heads for the Red River Formation, Bighorn Dolomite, and equivalent rocks of Ordovician age in the Northern Great Plains of Montana, North Dakota, South Dakota, and Wyoming

URI: https://pubs.usgs.gov/publication/ofr80730

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